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Mick Reeves Hunter kit build

Started by Turbine Tinkerer, December 06, 2013, 22:47:51 pm

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Turbine Tinkerer

Thanks for them Phil.

Did you use the outlines from the plan?
Can you get the retracts out through the gear doors alone or do you have a removable panel?


PhilH

Terry the answer to your questions are Yes No Yes.

I used the u/c door outlines as shown on the plan.  The area above the retract mount needs to be opened up to allow fitting and removal.  I made removable panels to close the area around the door, used proskin and Mick's very small screws to accomplish it.  You can just see part of the panel on picture no.3.
I will take a better picture later to show that area and you can go from there.   

Turbine Tinkerer

Thanks Phil.

I just wondered as the doors are much wider than the slots in the ribs. I just presumed that these would be the same width.

Not much done on the build today. Plugged up the old holes with dowel ready to drill the mounting holes in the new locations and took the extra balsa of the ribs that I added.

Turbine Tinkerer

Progress has been slow on the Hunter this week but now finally got the retracts mounted and got all the ribs back to original. I've made some ply wedges to pack the retracts of the original rails to allow the leg/wheel to retract into the correct position in the wing.

Turbine Tinkerer

Started looking at the flap servo mounting and linkage tonight.  The ripmax/flying legends manual states 100mm of travel on the flap for landing. I would have thought 45° adequate 60° maximum as its a split flap. 100mm sounds like a lot, what amount of travel is actually needed in degrees?

Turbine Tinkerer

Managed to sort out the flap servo mounting today. I opted to make a mount from 1/4 ply as the rib that it mounts in balsa and the opening as supplied was way bigger than a standard sized servo. I've put a  taper on it to get the servo squarer to the hinge line.

The 100mm of travel as quoted in the ripmax manual looks like it equates to approximately 45° of travel on my flaps. I've tried the linkage and all seems fine with 100% travel on the transmitter I have around 45° at the flap.

Next thing I'm going to do is mount the aileron servos so need to decide what I'm going to use.  Toying with the idea of using hitec 225 sized servos?  The thin wing servos look a little small although the torque figures are good. Standard sized servos will fit but will have to be moved forward making a longer linkage. Anyone got any thoughts on this?

HarryC

Hitec 225 generates the most complaints on the hitec forum on rcu.  I have had perhaps a dozen and they were all trouble. In my opinion avoid like the plague.

Turbine Tinkerer

I was just thinking of that size I would either use 5245's or the new 7245 high voltage model. Any feedback on these?

Turbine Tinkerer

Whilst I'm deciding on the aileron servos I thought I'd look at mounting the wings to the fuz. I've added some ply plates to the inside of the fuz for the wing dowels to go into and set the incidence.

Started looking at some 3 view drawings and it looks like it should have a slight amount of anhedral? What have other people done with theirs? 

THE BLACKBIRD

Yes the hunter has anhedral, had it on min, bit of a bitch to set up

Tony
The man that never made a mistake
Never made anything

Turbine Tinkerer

With the weather being as it has I've had a afternoon on the hunter.  Spent most of the time putting wings on and of checking angles etc. But hopefully it's paid of now as I have the former that the wing tubes mount onto glued into the fuz! The vpoxy is curing as I type. The wing tubes are coming out of the fuz at a downward angle at a rate of 5mm per 300mm. I've no idea if this is the correct angle as I can find no information on the plans or instructions but it is the right way so I can only presume its correct and generated automatically with the pre milled former. The wings snugly fit up to the moulded fuz sides. I also finished putting the ply blocks on the inside of the fuz that the wing dowels fit into and set the incidence.  I've checked these and they seem to be level across them. Some minor adjustments can be made to the dowels in the ribs if need be.

Turbine Tinkerer

The former is in and solid everything still lines up nicely so looks to be successful. 

The kit doesn't come with any outers for the wing tubes. It doesn't need to have them but should aid assembly at the field. I sourced some phenolic outers and I've made up some plates with a angled hole to accept the phenolic tube. These but up to the existing ply that carries the aluminium wing tubes. Took a bit of tweaking to the angles on the tube ends but now in and glueing up nicely.

Turbine Tinkerer

Moved onto the tail today so I can mount these and join the two fuselage halfs together knowing that everything is square and the incidences are correct.

The tail parts are all laser cut 3mm birch ply with some quite substantial lightning holes! Mick suggests glueing the ribs to the rear spar at 90° with cyno. I've opted to do this with aliphatic glue as the parts all fit together but are not a tight fit. I've only got half them in because my angle pieces are a little large. I'll add the rest when the glue has dried.

I'm undecided at the moment whether to use Micks single servo to drive the elevators or to use separate servos in each tail half.

Turbine Tinkerer

Finished framing up the tail and got the proskin on the top side. Whilst I was doing this I added provision for a 3rd hinge for the elevator I thought just 2 was a little optimistic. Also cut the rudder from the fuz to gain access to the tail joiner.


PhilH

You are making good progress Terry.  I only saw your pm today that you sent regarding the aileron linkage, we had a bereavement in the family so modelling matters haven't rated high on the priority list.
I used a straight piece of M3 threaded rod to connect the ball links, at the neutral position the link is level with the lower skin.  Don't like putting cranks in control rods so made yet another deviation from Mick's instructions.  The picture should make it clearer what I did.

Turbine Tinkerer

Sorry to hear you have had a bereavement Phil.

Essentially you have a long slot in the skin for the linkage to go into?

I need to make some decisions soon with the aileron and elevator servos.

Did a little more today and made a start on the elevators.  If I decide to mount the elevator servos in the tail I'll have to add some horns.

I feel it's moving on fairly quick now soon be able to look at joining the fuselage.

Turbine Tinkerer

Progress has been slow on the Hunter this week mainly working things out. On the plans the two tail halfs are joined with a aluminium rod that slides into brass tubes glued into the tail halfs. There's a dowel at the front to control incidence.  This setup allows a lot of movement of the tail. I think I'm going to replace the dowels with brass tubes and a rod that the tails can lock onto. I've also decided to use the essence of Micks elevator design with one servo in the centre controlling both sides although I have a few modifications in mind.

Turbine Tinkerer

Spent a bit of time today messing with the tail today. Made up a couple of pieces of 1/16 ply that I will eventually glue to the inside of the fuz to double up the fiberglass to carry the tail and elevator fixings. In the meantime I can use these to see how the tails go together and try the elevator mechanism.  I'm not over impressed with the elevator drive at the moment but there's room for some fettling yet. I think I need to fix the wires into the elevators and go from there. I have also got the two mating formers at the fuselage join glued in.

Turbine Tinkerer

I've had a look at the elevator drive and it appears that the rod with the slots in the end that the wires in the elevators go into is at fault. The main problem I had was that the elevators were not level with each other. Inspecting the slots in the rod showed that the slots dont line up with each other! I've remachined the slots level with each other but I've had to open the slots up to 4mm instead of 3mm. This looks much better now. Don't know whether to keep this or get some more material and make one up from scratch with 3mm slots?

A couple of photos of the fuz now its joined.  It really is a big model (long!)

Turbine Tinkerer

Couldn't resist putting it together! Here it is on its own wheels for the first time.

Pup Cam

It's looking Hunter shaped now and what a shape that is! :af

Alan
Still distracted by a 1953 AJS 16MS and now a 1939 BSA 250 too!

STORM


Thommo

Quote from: Turbine Tinkerer on February 09, 2014, 17:16:56 pm
Spent a bit of time today messing with the tail today. Made up a couple of pieces of 1/16 ply that I will eventually glue to the inside of the fuz to double up the fiberglass to carry the tail and elevator fixings. In the meantime I can use these to see how the tails go together and try the elevator mechanism.  I'm not over impressed with the elevator drive at the moment but there's room for some fettling yet. I think I need to fix the wires into the elevators and go from there. I have also got the two mating formers at the fuselage join glued in.


Wondered how the elevators were joined for single servo use, quite clever.
You mention fixing the wires to the elevators, don't they need to slide in & out as elevators move?
Model looks good assembled on it's wheels.  :af

Turbine Tinkerer

Quote from: Thommo on February 11, 2014, 11:44:19 am
Wondered how the in elevators were joined for single servo use, quite clever.
You mention fixing the wires to the elevators, don't they need to slide in & out as elevators move?
Model looks good assembled on it's wheels.  :af


Paul, The wires locate into holes in the root rib of the elevator all the sliding takes place the slot in the rod that goes through the fuz. When I first put it together I wondered how it would work with the angles involved but it certainly does. I need to make a new rod with the correct size slots in for the wires and also the slots need to be parallel to each other. The slot width looks really important if I'm going to have a good slop free drive.  I've got a 2.5mm end mill on order to make the slots hopefully this will cure my problems.  I considered glueing some feeler gauge into the 4mm slots I have now, this would give a nice hard surface for the wires to bear against but concerning if it were to come loose.

Turbine Tinkerer

Made these up tonight from 6mm birch ply. Hopefully these will make the wires that go into the elevators very secure.  Thinking of some sort of jig to make sure when I glue these into position they are both exactly level.

Turbine Tinkerer

Got the ply doublers that I made to help carry the tail fixings glued into place. Every thing lines up nicely and is square to the fin. Also made a new drive piece for the elevator with both the slots in line and a really good sliding fit on the wires.

Turbine Tinkerer

February 13, 2014, 20:24:06 pm #66 Last Edit: February 13, 2014, 20:36:22 pm by Turbine Tinkerer


A couple of videos to try and show the elevator setup not the best but you get the idea.  Oddly in the first one the elevators don't appear to be level with each other but they are???

https://www.youtube.com/watch?v=4QhBMHuo3Kw&feature=youtube_gdata_player

https://www.youtube.com/watch?v=gAdlKVrXV_U&feature=youtube_gdata_player










       


Turbine Tinkerer

A little more progress with the Hunter I managed to get the second skin on the tail and elevators, fitted the hinges into the elevators and added some balsa to the leading edge close up the hinge gap. Made holes in the bottom skin to allow access to the hinge pocket screws and the tail fixings (can hardly see these on the photos). Also cut into the fuz side to make access panels for the elevator servo and linkage. Finally glued the elevator drive brass bushes into place. I think I'm going to look at mounting the elevator servo next and work out linkage lengths to give me the desired elevator movement with 100% servo travel.

Turbine Tinkerer

I had a look at the elevator linkage today and although Micks offering would probably be sufficient I like a good solid link on my jets. Therefore I made this up from some fiberglass sheet and a all metal ball joint. It's weighs slightly more but I think the weight penalty is a fair compromise on something like this.

JohnMac

On my Sabre, I did away with all the complexity and put servos in the tailpane. I just plug them in now. No Slop and nothing to wear.
Works really well,
John

Turbine Tinkerer

A servo in each tailplane half would have been my preferred method John but I know people have used Micks method successfully. I did look at mounting twin servos but due to the tailplane thickness and rib spacing it would have been a lot of work. The system as I have it now looks to be good.

JohnMac

Yes, I have seen plenty fly OK with Mick's original system. Just watch out for wear as time goes by. You don't want the dreaded flutter.
John

Turbine Tinkerer

February 19, 2014, 20:13:16 pm #72 Last Edit: February 19, 2014, 20:17:28 pm by Turbine Tinkerer
I got the elevator servo mount glued into the fuz I also doubled it up with 6mm birch ply for the servo mounting screws. Worked the linkage out and I have 25mm of elevator travel at the root with 140% servo travel on the transmitter.  Its pretty much slop free and very positive all in all I'm quite happy with how its worked out. Just have to see how it performs over time. I will probably change the quick link for a metal ball joint before I fly it. A short video of it working.



https://www.youtube.com/watch?v=HiLVzWhVpSA&feature=youtube_gdata_player



Turbine Tinkerer

Thanks Gary.

The rudder next, Micks design isn't hinged/actuated in the conventional way. There's a single hinge at the top and the bottom sits directly on top of the servo making the second hinge point. I'm a little concerned that this system is 1-1 drive. 

Here's the parts supplied to mount it. There's 3 long balsa parts, one of these goes into the rear of the fuz the second into the front of the rudder and the third goes onto the front of this and later shaped into a radius to seal the hinge line. First impressions are that they might need some modifications as the holes for the top hinge point don't line up?


Turbine Tinkerer

After a 8 week break for various reasons I've got back on the Hunter. Carrying on with the back end I decided to look at the tail tips. These are vac formed parts that sit on the ends with not a lot of glue area! I made up a balsa rib to sit inside the vac forming and glue onto the end rib where the proskin ends. This has worked out quite well with minimal sanding/filling required. I'll carry on with the rudder next.

Turbine Tinkerer

And a picture of the completed tail tip (no filler yet) managed to get both sides done and also added some small proskin pieces to the rear of the tails to fair in the elevator mechanism.  Leading edges stillto add. These are just balsa sanded to shape.

Turbine Tinkerer

Added the balsa leading edges to the tail and shaped it to suit. Looks quite good at the moment at the join of the proskin and vac formed tip. I'm planning on over wrapping the leading edges with 25g glass cloth and epoxy at a later stage.

Turbine Tinkerer

May 06, 2014, 20:39:23 pm #78 Last Edit: May 06, 2014, 20:41:18 pm by Turbine Tinkerer
Finally bit the bullet and tackled the rudder. After some slight modifications to the supplied balsa parts all went together ok. I had to make some new servo mounts as I've fitted my servo the opposite way around to what Mick suggests to aid clearance. I've used a Hitec 225 at the moment but will probably change this for a 7245 for its high voltage capability.

Turbine Tinkerer

A short video of the rudder in action. This is 70% travel on the transmitter giving about 35mm of travel each way at the root.


http://youtu.be/ovcYzrajEVA